The purpose of the proposed research is to apply modern psychophysical methods to the study of taste function in human subjects under conditions of controlled adaptation. Specifically, we will study: A. Simple adaptation. The time course of adaptation and recovery from adaptation to compounds representative of the four basic tastes. B. Cross adaptation. The effect of adaptation to a particular sapid substance on the taste magnitude and quality of substances having the same or different taste qualities. C. Measure the temporal modulation transfer function for taste and model the temporal properties of the gustatory system.